Arterial cannulation is used widely in the clinical management of critically ill adults, with intra-arterial cannula placement second in frequency only to intravenous cannulation. It provides an uninterrupted display of pulse contour and continuous beat-to-beat haemodynamic measurement. This data can be invaluable for effective clinical management, such as the reliable titration of supportive medications. Numerous patient conditions, including morbid obesity, burns or trauma to the extremities and shock can cause non-invasive blood pressure measurements to be inaccurate, and thus necessitate invasive blood pressure monitoring. The procedure of arterial cannulation comes with some risk, such that the need must be weighed against the risk to the patient. Arterial cannulation may be performed on a number of vessels including the radial, femoral, axillary, brachial, ulnar, dorsal pedis, tibial posterior and temporal arteries. Arterial cannulation is also essential for gaining access to the arterial system for angiography and placement of guidewires, balloon pumps, catheters and stents.
This disclosure focuses on arterial cannulation, and in particular embodiments on femoral artery cannulation, which has numerous advantages over cannulation of other sites. Femoral cannulation provides a pulse contour approximating aortic with minimal thrombotic risk. There is little evidence to show increased incidence of catheter-related systemic infection at this site.
The femoral artery lies in a neurovascular bundle lateral to the femoral vein and median to the femoral nerve (as seen in FIG. 1). The femoral artery is palpated midway between the anterosuperior iliac spine and the symphysis pubis. Collateral circulation exists via a number of anastomoses, and the large vessel diameter allows catheter longevity twice that of radial catheters. Prospective and retrospective studies detail the relative safety of this site for hemodynamic monitoring. A potential exists, however, for extraperitoneal hemorrhage, vascular injury from common branch entry, and cannulation hematoma. Femoral artery catheter complications, though infrequent, are complicated, difficult to identify, and may be associated with significant mortality. The femoral artery usually can be cannulated, even during profound shock states.
An important application for the procedure is emergent or urgent cannulation of the femoral artery for subsequent placement of a REBOA balloon or intraaortic balloon pump. REBOA is Resuscitative Endovascular Balloon Occlusion of the Aorta and is a lifesaving device for use in patients with pelvic fractures, penetrating injuries, life threatening hemorrhage, ruptured abdominal aortic aneurysms, and other emergency conditions. REBOA may have the greatest benefit when deployed early, and has been applied in the field (pre-ambulance) in Europe. There is clear military importance in deployment of REBOA in the field. An intra-aortic balloon pump is used to support patients in cardiogenic shock, and is also often deployed under urgent or emergent conditions.
Femoral artery cannulation is a valuable procedure, but at present clinicians with advanced training must perform the procedure. Cannulation and sheath placement in the femoral artery currently requires a physician with advanced training (e.g., training in vascular surgery, trauma surgery, interventional radiology or interventional cardiology) and involves multiple needle, scalpel and wire exchanges (Seldinger technique, see FIG. 2). In an emergency setting, the femoral pulse may be absent or decreased due to hypotension which further complicates accurate localization for cannulation. The absence or limited availability of properly trained clinicians in all emergency or military settings limits the current applicability of REBOA or other invasive resuscitative or monitoring techniques. Earlier pre-hospital use of these techniques would increase survival, but requires accurate femoral artery cannulation in settings where the available personnel lack the training for conventional femoral artery cannulation.
Therefore, there remains a need in the art for systems and methods that will enable arterial cannulation, and more particularly femoral artery cannulation, in an emergency setting by persons lacking the traditional advanced training in arterial cannulation, and that allow such arterial cannulation to be carried out quickly, easily, effectively, and safely by such persons.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form any part of the prior art.